HALLE, Germany -- Defending champion Tommy Haas advanced to the quarterfinals of the Gerry Weber Open on Thursday by outlasting Ernests Gulbis 7-6 (5), 6-4.
Second-seeded Richard Gasquet swept past Jurgen Melzer 6-3, 6-1 and sixth-seeded Philipp Kohlschreiber joined Gasquet in the last eight by beating German compatriot Tobias Kamke 6-4, 6-3. Kohlschreiber won the Halle event in 2011. The tournament is a grass-court tune-up for Wimbledon.
Gasquet fired an ace to close out the first set and dominated the second. Down 15-40 in the final game, he won the next four points to close it out.
Haas, who won the Halle event in 2009, is enjoying a second spring at age 35 and is coming off a quarterfinal appearance at the French Open.
After losing the first set to a forehand winner by Haas, Gulbis broke his racket in anger and decided to change his shoes and shirt as well.
He lost the first three points of the second set but managed to hold. Haas must have felt frustrated, since he had failed to convert 16 straight break points until then.
The break came on the 17th and Haas finally went up 3-2 and stayed ahead for good. The German never faced a break point and overcame 15 aces by his Latvian opponent.
"Overall, I played a good match. But I would have been very upset if at the end I'd lost because I couldn't take all those chances," said Haas, who also had a first-round bye.
Haas is the oldest player in the top 100 and is looking for his second title of the year. He is now ranked No. 11. He won last year's title in Halle by beating Roger Federer.
Kohlschreiber's next opponent will be Mikhail Youzhny. Gasquet will play eighth-seeded Florian Mayer, who beat another Mayer, Leonardo of Argentina, 6-2, 6-3.
Florian Mayer is a German who beat Gasquet in Wimbledon last year.
"He returns very well, he doesn't give you much space to manoeuvr him around the court," Gasquet said of his next opponent.
Gasquet had a bye into the second round and said he had used the time since Sunday to practice and adjust to grass.
"It's good to practice with good players, I really like playing on grass and it's important to prepare for Wimbledon," the Frenchman said. "But this is also a big tournament in itself and I want to do well."
Gasquet is playing in Halle for the first time in six years and said he was glad to be back.
"I have great memories, I beat Tommy Haas here in a Davis Cup match over five sets (in 2006) -- one of the best matches of my career," Gasquet said.
Gasquet was pleased with his opener.
"I played very well. I served big and I returned well," said Gasquet, who landed 88 per cent of first serves. "The grass here is faster than in England. I am glad I played that well."
Haas next plays Gael Monfils, while the top-seeded Federer meets Mischa Zverev in Friday's quarterfinals.